I've been denied entry to a restaurant because I'm a foreigner, and my employer pays me less than Korean?

This is a real and frustrating issue, and there are some protections, though Korea does not yet have a single comprehensive anti-discrimination law, so it works through a few channels. On the pay gap: the Labor Standards Act prohibits discriminatory treatment in working conditions based on nationality, so paying a foreign worker less than Korean colleagues for the same work can be unlawful. Report it to the Ministry of Employment and Labor, whose counseling line is 1350 with multilingual support, and they investigate wage and working-condition complaints and can order corrections and back pay. Gather evidence first, such as your contract, pay records, job description, and proof that colleagues in the same role are paid more.

For the restaurant entry refusal and discrimination more broadly, the main avenue is the National Human Rights Commission of Korea (국가인권위원회), which accepts complaints of discrimination based on nationality and race and can investigate and issue recommendations; you can file with them directly. There are also foreign worker support centers and NGOs, free legal counseling through the Korea Legal Aid Corporation at 132, and the Danuri helpline at 1577-1366 if you are in a multicultural family. Practically, document everything with dates and details, start with 1350 for the wage issue and the Human Rights Commission for the discrimination, and consider a consultation with a labor lawyer (some offer free initial sessions through the bar association or a Global Center). Enforcement is imperfect and change can be slow, but these bodies do act on well-documented cases, so you are not without recourse.